It could have been why he was left off the Atlantic Coast Conference’s all-freshman team. Teammate Ryan Anderson (11.2 points, 7.4 rebounds) was a no-brainer, but Clifford may have gotten bumped by the overall play of Virginia Tech’s Dorian Finney-Smith (6.3 points, 7.0 rebounds).

Clifford made note of it all during the offseason, and came out strong on the Eagles’ season-opening four-game European trip.

“I was really looking forward to proving to people that I could play,” said Clifford, whose Eagles take on Maryland in an ACC matchup Tuesday night at Conte Forum. “I think there was a lot of doubt last year about the things I could do. So I really took it upon myself in the offseason to fix that. I was really looking forward to helping my team as much as I can.”

However, an injured left knee has slowed Clifford this season, probably the most frustrating part of an all-around difficult sophomore campaign.

After playing all 31 games as a freshman, he has been limited this season. He missed two games in December while dealing with knee and ankle injuries. His minutes have been sporadic over the 22 games he has played, and he has made only 10 starts.

In practice, coach Steve Donahue and Eagles trainers have been cautious, limiting him to eight-minute blocks. The damage in his left kneecap — caused by a condition called chondromalacia — reached the point earlier this month that he needed a cortisone shot to continue playing.

Last week, in a win over Wake Forest and a loss to Florida State, Clifford started consecutive games for the first time since November.

He had just 4 points and four rebounds total in the two games, but he played more minutes than he has in a month.

“It’s been frustrating,” he said. “I’m doing better. Just trying to get back into the swing of things now. I think everything’s starting to come around for me, I’m starting to work out more, get into the flow of the game.”

Without him, the Eagles are forced to go with a smaller lineup and are paying the price on the boards. No one feels it more than the 6-foot-8-inch Anderson, who’s averaging 8.6 rebounds a game and often is the only true front-court player on the floor for the Eagles (11-14, 3-9).

“It makes my job a lot harder,” said Anderson, who had 10 points and 11 rebounds against Florida State for his seventh double-double of the season. “I wish he could be out there with me. A 7-foot presence is a big presence. I think I definitely feel the loss of Dennis the most. I’d like him to be back as soon as possible, but he’s got to take care of his body.’’

The Eagles have struggled on the glass all season, and are being outrebounded in ACC games by five a night.

Last month, Maryland posted a 64-59 victory over the Eagles as the Terrapins controlled the glass behind 7-footer Alex Len’s 13 rebounds. Clifford played 19 largely hollow minutes off the bench in the loss as Anderson was physically overmatched.

“I think we felt we would be very good about where we are physically inside,” Donahue said. “But Maryland has not only length, but bigger, thicker kids and then big size at the guards.

“I think that’s all part of our challenge, especially as we are young here, growing into being physical players. We basically played seven scholarship players, and they are all freshmen and sophomores, and I think they are not there physically yet.

“Now, Dennis is starting to get more healthy. When he plays, I think we are a different team defensively. And I think he’s added that part and hopefully we can get some minutes out of him on Tuesday night.’’

Clifford likely will be in the starting lineup against Maryland, feeling more comfortable if not completely healthy.

“I think it’s something that I can play through,” Clifford said. “It’s been bothering me for a little while now. It just kind of crept up on me this season. For the future, I just think it’s something I have to deal with.

“When I’m out there, I just think about how much I love being out there. The same thing with practice. When I get the OK, I don’t think about anything else except how much I love to play. It’s kind of like this has been put in perspective for me, just sitting out, watching. Then when you get out there, it’s like, ‘Wow, this is what I love.’ So you just want to give it 110 percent.”

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